1. Field of the Invention
The present invention relates generally to the fields of molecular medicine and drug delivery and, more specifically, to molecules that selectively home to the vasculature of mammary tissue.
2. Background Information
A major hurdle to advances in treating breast cancer is the relative lack of agents that can selectively target the cancer while sparing normal tissue. For example, radiation therapy and surgery-, which generally are localized treatments, can cause substantial damage to normal tissue in the treatment field, resulting in scarring and loss of normal tissue. Chemotherapy, in comparison, which generally is administered systemically, can cause substantial damage to organs such as bone marrow, mucosae, skin and the small intestine, which undergo rapid cell turnover and continuous cell division. As a result, undesirable side effects such as nausea, loss of hair and drop in blood cell count can occur as a result of the systemic treatment of a breast cancer patient with a chemotherapeutic agent. Such undesirable side effects often limit the amount of a treatment that can be safely administered, thereby hampering survival rate and impacting the quality of patient life.
As an example, estrogen receptor positive cancer often is treated with the estrogen receptor modulator agent, tamoxifen. However, potential risks associated with tamoxifen treatment include endometrial cancer and thromboembolic disease. Similarly, the use of the platinum agent, cisplatin, can be limited by the severe nausea, vomiting, neuropathy and myelosuppression that accompany administration of this drug. Other agents for treatment of breast cancer similarly are accompanied by undesirable side effects due to the fact that they cannot be specifically delivered to the breast without also reaching other organs of the patient.
It is clear that there is a strong genetic component to the etiology of most types of malignant tumors, including breast cancer. Mutations in the tumor suppressor genes BRCA-1, BRCA-2 and p53, for example, contribute to predisposition to breast cancer. Familial occurrence, tests for mutated tumor suppressor genes and the diagnosis of lobular carcinoma in situ define a population of women at high risk of developing breast cancer. Currently, the only effective strategy for preventive treatment of these women at high risk is preventive mastectomy. Thus, there is a need for simpler and less invasive procedures for selectively ablating breast tissue, for example, as a preventive measure in women at high risk or to treat pre-malignant or early breast cancer.
The present invention satisfies this need by providing molecules that selectively home to breast vasculature and which are suitable for selectively targeting agents for cell ablation or other chemotherapeutic agents to breast tissue, particularly to breast vasculature. Related advantages also are provided.